What is the Alnico Magnet?
Alnico magnet is an acronym referring to a family of iron alloys which in addition to iron are composed primarily of aluminium (Al), nickel (Ni) and cobalt (Co), hence al-ni-co. They also include copper, and sometimes titanium. Alnico alloys are ferromagnetic, with a high coercivity (resistance to loss of magnetism) and are used to make permanent magnets. Before the development of rare earth magnets in the 1970s, they were the strongest type of magnet. Other trade names for alloys in this family are: Alni, Alcomax, Hycomax, Columax, and Ticonal.

The composition of alnico alloys is typically 8–12% Al, 15–26% Ni, 5–24% Co, up to 6% Cu, up to 1% Ti, and the balance is Fe. The development of alnico began in 1931, when T. Mishima in Japan discovered that an alloy of iron, nickel, and aluminum had a coercivity of 400 oersted (Oe) (32 kA/m), double that of the best magnet steels of the time.

Alnico alloys make strong permanent magnets, and can be magnetized to produce strong magnetic fields. Of the more commonly available magnets, only rare-earth magnets such as neodymium and samarium-cobalt are stronger. Alnico magnets produce magnetic field strength at their poles as high as 1500 gauss (0.15 tesla), or about 3000 times the strength of Earth’s magnetic field. Some brands of alnico are isotropic and can be efficiently magnetized in any direction. Other types, such as alnico 5 and alnico 8, are anisotropic, with each having a preferred direction of magnetization, or orientation. Anisotropic alloys generally have greater magnetic capacity in a preferred orientation than isotropic types. Alnico’s remanence (Br) may exceed 12,000 G (1.2 T)[clarification needed], its coercivity (Hc) can be up to 1000 oersted (80 kA/m), its energy product ((BH)max) can be up to 5.5 MG·Oe (44 T·A/m). This means alnico can produce a strong magnetic flux in closed magnetic circuit, but has relatively small resistance against demagnetization.

Alnico alloys have some of the highest Curie temperatures of any magnetic material, around 800 °C (1,470 °F), although the maximum working temperature is normally limited to around 538 °C (1,000 °F).They are the only magnets that have useful magnetism even when heated red-hot.This property, as well as its brittleness and high melting point, is the result of the strong tendency toward order due to intermetallic bonding between aluminium and its other constituents. They are also one of the most stable magnets if they are handled properly. Alnico magnets are electrically conductive, unlike ceramic magnets.
 
Cast Alnico Magnet Feature:
1. Using patterns and simple moulding techniques, Cast AlNICo Magnet can be cast to form a vast range of complex shapes and sizes at an economical cost.

2. Eclipse Magnetics Alnico magnets are ideal for high temperature applications up to 550ºC

3. Cast AlNICo Magnet is very stable, has good corrosion resistance and a typical hardness of 50 Rockwell C. Once cast, the material is so hard that the only machining possible is grinding

4. Cast AlNICo Magnet represents the most versatile magnet material available. The range of properties can be accurately designed for specific applications by changes to element analysis and heat treatment.
 
Alnico Magnet Application:
1. ABS braking system magnets
2. ABS braking system magnets
3. Reed switch operating magnets
4. Electricity meter damping magnets
5. Holding/clamping applications
6. Microwave applications
7. Weighing scale damping magnets
8. Electropermanent systems
9. Calibration magnets
10. Heat treatment jigs and fixtures
 
Magnetic properties of Cast AlNiCo magnet:

Tags: Alnico Magnet, NdFeB Magnets